Cancun (Mexico), Oct 31 : Playing her first tournament since splitting with coach Pere Riba, no.3 seed American Coco Gauff kicked off her WTA Finals singles campaign with a bang after defeating No.6 seed Ons Jabeur 6-0, 6-1 here. Monday's win was Gauff's first at the season-ending championships, having gone 0-6 in singles and doubles last year in Fort Worth. It is also her eighth Top 10 win of the year. Only her next opponent, Iga Swiatek, has tallied more, WTA reports. Gauff has now won 50 matches this season, with eight coming against Top 10 opponents. She is the first teenager to win 50 or more matches in a single season since Caroline Wozniacki in 2009. She is also the first teenager to tally a singles victory at the WTA Finals since Wozniacki and the first American teenager to do so since Venus Williams in 1999. Gauff will face No.2 Swiatek next in what will be the 10th career meeting between the two young champions. Swiatek opened play in the Chetumal Group with a resilient comeback win over Marketa Vondrousova, rallying from 5-2 down to win 7-6(3), 6-0. In a meeting of 2023 major champions, Swiatek's deep, forceful strokes bested Vondrousova's customary guile. Swiatek finished in a blur, winning the last four games of the first set, the tiebreak and all six games in the second. The 22-year-old Pole is now 3-0 versus Vondrousova and has the most career victories over the WTA Finals qualifiers, as well as the most match-wins this year, nine. /IANS